Coil overs are an inbetween rather than changing leaves. My Suburban has them in the rear, and frankly I do not even notice them. Sure has a stiff ride, which I like.
Coil overs give boost for sagging springs, or heavier than usual loads. I think they are worth the money, they pop right on, and you do not change them untill the shocks need changing. In the rear, that takes some real time.